Polyethylene - Iyini? Ukusetshenziswa polyethylene

Kuyini PE? Yiziphi izici zayo? Injani ukukhiqizwa polyethylene? Lena imibuzo ethakazelisa kakhulu okumelwe icatshangelwe kulesi sihloko.

ulwazi olujwayelekile

Polyethylene - a ikhemikhali okuyinto neketanga zama-athomu carbon, ngamunye okuyinto ixhunywe amabili molecule e-hydrogen. Nakuba kunezinkolo ukwakheka efanayo, kodwa kukhona izinguqulo ezimbili. yabo ingafani isakhiwo zabo, futhi ngenxa yalokho, izakhiwo. Eyokuqala neketanga komugqa lapho degree of polymerization idlula Inkomba ayizinkulungwane eziyisihlanu. Eyesibili isakhiwo - a amagatsha ka 4-6 carbon ngama-athomu, enamathiselwe iketango lemcoka indlela ngaphandle kokubonisana nomkayo. Njengoba uhlaka etholwe polyethylene komugqa? Lokhu kufezwa ngokusebenzisa yelikhono ekhethekile, ezithinta polyolefins at amazinga akahle okushisa (kufika ku-150 degrees Celsius) nokucindezelwa (kufika ku-20 izikhathi eziphindwe). Kodwa kuyini na? Siyazi yawo yamakhemikhali izakhiwo, nokuthi yiziphi ke ngokwenyama?

Kuyini lokhu?

Polyethylene - polymer Thermoplastic, lapho inqubo crystallization wenziwa ezingeni lokushisa esingaphansi lokususa 60 degrees Celsius. Akukhona obala ungqimba obukhulu akuyona wetted ngamanzi, ezihogelwayo ekamelweni lokushisa ayiphazamiseki. Uma izinga lokushisa udlula 80 degrees Celsius, ukuvuvukala Kwenziwa kuqala, bese kwamazinyo ukuze hydrocarbon enamakha Halogen nemikhiqizo. Polyethylene - into umelana enqabayo ithonya izixazululo of acid, nosawoti kanye alkalis. Kodwa uma izinga lokushisa udlula degrees 60 Celsius, kungaba ngokushesha impela, ubhidlize nitric futhi acid sulfuric. Ukuze imikhiqizo kunenze nisondelane polyethylene zingase oxidants kusetshenzwe, kulandele isicelo we izinto ezidingekayo.

Injani ukukhiqizwa polyethylene?

Ngenxa yale njongo:

• Indlela ephezulu ingcindezi (ukuminyana ongaphakeme). Polyethylene kudalwa ngomfutho ophakeme, okuyinto in the uhla kusuka 1 000 kuya ku-3, 000 eziphindwe at lokushisa 180 Celsius. Njengoba umoya-mpilo lisebenza njengesimemo umqalisi.
• Indlela ingcindezi ongaphakeme (high density). Kulokhu, polyethylene kudalwa ngesikhathi ingcindezi okuyinto eziphindwe okungenani ezinhlanu kanye lokushisa 80 degrees Celsius Usebenzisa kuphela organic futhi Ziegler-Natta yelikhono.
• Futhi ngokwehlukana lwento umjikelezo zokukhiqiza polyethylene, okukhulunywe ngaso ngenhla. Kuyinto Lesisemkhatsini phakathi kwezindawo lokuqala nelesibili.

Kumele kuqashelwe ukuthi le akuyona kuphela ubuchwepheshe asetshenziselwa ukuthi. Ngakho, akuve kuvamile ukuba nokuningi ukusetshenziswa metallocene yelikhono. Okwakushiwo lo mshini ukuze ngalo kuzuzwe isisindo enkulu polymer, ngokwenza kanjalo wandise amandla komkhiqizo. Kuye uhlobo lwesakhiwo futhi izakhiwo ayadingeka uma usebenzisa monomer, futhi isetshenziselwa ukhethe indlela i-reception. Futhi, ingaba nomthelela izidingo ukuncibilika lokushisa, ukuqina, ubulukhuni kanye kwabantu.

Kungani kunomehluko eqinile?

Isizathu esiyinhloko umehluko izakhiwo - ke branched macromolecules. Ngakho, elikhulu linjalo, njengeliyiZwi engenhla nengezansi yakhe crystallinity polymer kuyaqina. Kungani kubalulekile lokhu? Iqiniso ukuthi izakhiwo mechanical polyethylene ezikhulayo kanye ukuminyana yayo nesisindo yamangqamuzana ezinto eziphilayo. Ake sibheke isibonelo esheshayo. Ishidi polyethylene has rigidity eside kanye nokuvuleleka. Kodwa uma usebenzisa ephansi kwabantu indlela, indaba okuholela kuyodingeka Ukuzivumelanisa nezimo impela okuhle futhi ukubonakala isihlobo ngalo. Kungani yathela ububanzi ezihlukahlukene kangaka? Ngenxa umehluko ezimweni yokusebenza. Ngokwesibonelo, i-polyethylene ubhekana imithwalo ukushaqeka. Wabuye uyazibekezelela frost. Amazinga okusebenza uhla le nto - kusuka -70 kuya +60 Celsius. Nakuba izitembu ngamanye aguqulelwe umyela kuyiwa - futhi kusukela -120 kuya +100. Lokhu kuthonywa kwabantu polyethylene ne oyiyo ezingeni yamangqamuzana ezinto eziphilayo.

I ngokucacile-material

Kufanele kuqashelwe yayinesithiyo esisodwa - ukuguga okusheshayo polyethylene. Kodwa lokhu silungiswa kalula. Ukwandisa inkonzo nokuphila ibangelwa izithasiselo ekhethekile, Antioxidants, endimeni ezingasetshenziswa isinyathelo carbon omnyama, phenols noma ama. Kufanele kuphawulwe nokho, ukuthi into ephansi kwabantu viscous ngaphezulu, okwenza kube lula ukuba kusetshenzwe ku imikhiqizo. Ingasaphathwa, futhi izakhiwo kagesi. Polyethylene ngoba polymer non-polar eliphezulu high-imvamisa Kwe-dielectric Heating. Ngenxa yalokhu tangent njalo futhi ukulahlekelwa ngu kancane kokushintsha nomswakama izinguquko, izinga lokushisa (in the ezahlukene -80 kuya +100) kanye nobuningi yasendle kagesi. Lapha kufanele uqaphele esinye isici. Ngakho, uma ku polyethylene kukhona kulethe izinsalela, ke sithuthukisa Kwe-dielectric Heating nokulahlekelwa tangent, okuholela ukuwohloka ezithile nangokuvikela izakhiwo. Nokho, thina manje isimo jikelele sabuyekezwa. Manje ake unake imininingwane.

Kuyini high density polyethylene?

Lokhu kwaziswa nokunwebeka ukukhanya crystallizable ukumelana kabani ukushisa ungaphakathi uhla kusuka -80 kuya +100 degrees Celsius. It has a ebusweni shiny. Vitrification uqala at -20. A ukuncibilika - in the uhla 120-135. Isici kuyinto enhle amandla umthelela nokushisa ukumelana. inhlanganiso polyethylene kakhulu kuthinte izakhiwo okuholela. Ngakho, nge likhula ngamandla, ukuqina, ubulukhuni nokuzabalazela zamakhemikhali. Kodwa ngesikhathi esifanayo kunciphisa nokuthambekela yokwelula futhi permeability ukuba amagesi futhi evala. Kumele ungangena ukuthi kwenzeka ngesikhathi umthwalo isikhathi eside waphawula. polyethylene njalo is eziphila inert, futhi kungenziwa kalula kabusha. Yikuphi iyasiza kakhulu ezweni lanamuhla. Ukukhuluma mayelana nokusetshenziswa polyethylene, kufanele kuphawulwe ukuthi isetshenziswa womshini iphakeji iziqukathi. Ngakho, cishe ingxenye eyodwa kwezintathu ukukhiqizwa uyaphuma ukudala udini esitsheni buhlungu, esetshenziswa embonini yezokudla, izimonyo, yezimoto, umthengi, amandla Amasimu namafilimu. Kodwa kungatholakala uma udala tube nogwali izingxenye. Inzuzo esibalulekile salokhu okokusebenza ukuqina yayo, izindleko ongaphakeme kanye kalula Welding.

Okuphansi ukuminyana polyethylene

Lokhu nokunwebeka impahla ukukhanya crystallizable nge ukumelana ukushisa (mthwalo) ku uhla kusuka -120 kuya +90 degrees Celsius. Izakhiwo nazo engaphansi kakhulu phezu kwabantu impahla okuholela. Ngakho kukhona nokwanda wamandla, ubulukhuni, ukuqina kanye ukumelana amakhemikhali. Ndawonye nale ukujiya polyethylene kubathinta kabi amandla umthelela, ukunwebeka, crack ukumelana naso futhi kwenze permeability ukuba amagesi futhi evala. Ngaphezu kwalokho, akuhlukile ukuzinza ntathu kanye nomthelela kakhulu ezimbi ngezinye imithwalo iphansana. Kufanele kuqashelwe ngempela okusezingeni eliphezulu ukumelana zamakhemikhali kakhulu izici Kwe-dielectric Heating. Kusukela negative - on polyethylene kukhona amafutha ezimbi, amafutha kanye emisebeni ultraviolet. Ngokwemithetho yempilo inert, kungenziwa kabusha kalula. Futhi namanje lungachazwa njengoba ukumelana emisebeni. Isicelo ephezulu ukuminyana polyethylene kungabonwa kakhulu uma udala lobuchwepheshe, ukudla namafilimu wezolimo. Nakuba Yiqiniso, akuyona VO.

polyethylene komugqa

Kuyinto impahla nokunwebeka crystallizes. It ongakwazi ukumelana namazinga okubanda afinyelela ku-118 degrees Celsius. Enye inzuzo obalulekile le nto umelane layo kwemifantu, ukushisa ukumelana namandla umthelela. Isetshenziselwa yokukhiqiza amaphakheji, izitsha kanye iziqukathi. Yini inikeza PE? Izimfanelo le nto kuphezulu kakhulu uma kuqhathaniswa ubuciko ngaphambi ezihlelwa indlela ingcindezi ongaphakeme. Ngakho-ke, yena unalo impahla kuhle. Kodwa namanje, njengoba umthetho, asikwazi kulinganiswa nge polyethylene ephezulu ingcindezi.

Njengoba kungashiwo omelelwa ezibonakalayo?

Ngakho, sinezinto ihlanganiswa izinhlobo eziyisisekelo polyethylene. Ngayiphi ifomu ezidalwe? Ethandwa kakhulu - ishidi polyethylene ne ifilimu. Lawa mafomu kungenzeka ekhiqizwa kusuka kunoma iyiphi ukuminyana impahla. Nakuba namanje kukhona izintandokazi ezithile. Ngakho, ukwenziwa amabhayisikobho nezimo futhi mncane kabanzi ongaphakeme ingcindezi indlela. Ububanzi impahla etholwe, ngokuvamile ifinyelela 1400 mm, ubude - amamitha angu-300. Ukuthuthukiswa ongaphakeme ukuminyana polyethylene ne baqinisa Nokho, ngokushesha baqalaza asetshenziselwa izakhiwo okuyinto akumelwe bahlukunyezwe: amashidi esifanayo, kwamiswa futhi ukubunjwa izihloko nokunye.

isiphetho

Futhi ekugcineni, ingasaphathwa imibhalo zokulawula, owawuthi kanye polyethylene kukhiqizwa. GOST 16338-85 ababenyathelisa okudaliwe ngomfutho ongaphakeme. Isebenza ngaphezulu ngo-1985. GOST 16337-77 elawula izimpikiswano ezihlobene polyethylene ephezulu ingcindezi. Usemdala nakakhulu futhi sihlehlela emuva ngonyaka 1977. Le mibhalo normative aqukethe ulwazi mayelana nezidingo mathiriyeli kuyiphi ekhiqizwa futhi ifilimu, emabhokisini kanye neminye imikhiqizo ehlukahlukene. Ngaphezu kwalokho, kufanele kuphawulwe anhlobonhlobo isicelo imikhiqizo etholakale nezinhlobo zalo ukwehluka. Ngakho, ngokwesibonelo, evame kakhulu kwagcizelela polyethylene ifilimu. engavamile wabo ukuthi ukushuba efanayo ikhanda namahlombe ngenhla izakhiwo zabo ngaphandle namasampula omkhiqizo ezivamile. Of okufanayo kwagcizelela polyethylene amafilimu wenze zokudla kuhlanzekile yini, izikhwama kanye nezinye izinto eziningi eziwusizo. izakhiwo zabo etholakala ngokwethula lokuluhlaza obalulekile kusuka ngomhla ka Imicu yotshani zemvelo noma zokwenziwa.